| View previous topic :: View next topic   | 
	
	
	
		| Author | 
		Message | 
	
	
		daj95376
 
 
  Joined: 23 Aug 2008 Posts: 3854
 
  | 
		
			
				 Posted: Sun Oct 26, 2008 6:24 pm    Post subject: No XY/XYZ-Wings: Set A Puzzle 1 | 
				     | 
			 
			
				
  | 
			 
			
				I've only had moderate success generating puzzles for the forum. It seemed that every time I went beyond XY/XYZ-Wings then the puzzles weren't suitable. Then, a recent discussion about how an XY-Wing was too easy to solve a puzzle resulted in other techniques being used to find the solution.
 
 
I went back and generated a number of puzzles that could be solved using XY/XYZ-Wings. Then I checked them hoping to find some that could/might be solved with other techniques. See what you think about this puzzle!
 
 
BTW: no cheating and substituting 3-cell XY-Chains for XY-Wings   
 
 
 	  | Code: | 	 		   +-----------------------+
 
 | . . . | . . 2 | . . . |
 
 | . . . | 9 . . | 4 5 8 |
 
 | . . . | 4 . . | . . . |
 
 |-------+-------+-------|
 
 | . 9 4 | 6 3 . | . 8 . |
 
 | . . . | 5 4 . | . 3 . |
 
 | 5 . . | . . 8 | . . 4 |
 
 |-------+-------+-------|
 
 | . 3 . | . . . | 2 6 . |
 
 | . 6 . | 2 5 . | 7 4 . |
 
 | . 5 . | . . 6 | . . . |
 
 +-----------------------+
 
 | 	 
  | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		nataraj
 
 
  Joined: 03 Aug 2007 Posts: 1048 Location: near Vienna, Austria
  | 
		
			
				 Posted: Sun Oct 26, 2008 7:06 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				A puzzle that can be solved without xy-wing. Just my cup of tea!
 
 
After basics, kite (7) row 6 and col 6: r2c2<>6
 
 
Then ... (you guessed, right?)
 
 	  | Code: | 	 		  
 
+--------------------------+--------------------------+--------------------------+ 
 
| 13689   4       5        | 138     168     2        | 39      7       16       | 
 
| 12367   12      167      | 9       167     137#     | 4       5       8        | 
 
| 136789  178     16789    | 4       1678    5        | 39      2       16       | 
 
+--------------------------+--------------------------+--------------------------+ 
 
| 127     9       4        | 6       3       17*      | 5       8       27       | 
 
| 2678    278     678      | 5       4       9        | 1       3       27       | 
 
| 5       17      3        | 1-7     2       8        | 6       9       4        | 
 
+--------------------------+--------------------------+--------------------------+ 
 
| 179     3       179      | 18      189     4        | 2       6       5        | 
 
| 189     6       189      | 2       5       13#      | 7       4       39       | 
 
| 4       5       2        | 37*     79      6        | 8       1       39       | 
 
+--------------------------+--------------------------+--------------------------+
 
 | 	  
 
Using the strong link (3) in col 6, r9c4 and r4c6 work together:
 
 
if r9c4=3 then r2c6=3 then r4c6=7 and 7 in r6c4 is toast!
 
 
...singles after that.
 
 
Nice one!! | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		keith
 
 
  Joined: 19 Sep 2005 Posts: 3355 Location: near Detroit, Michigan, USA
  | 
		
			
				 Posted: Sun Oct 26, 2008 7:41 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				 	  | Quote: | 	 		  BTW: no cheating and substituting 3-cell XY-Chains for XY-Wings     | 	  
 
 
We meet at dawn!  I will slap you with my extended wing!
 
 
Keith | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		daj95376
 
 
  Joined: 23 Aug 2008 Posts: 3854
 
  | 
		
			
				 Posted: Sun Oct 26, 2008 8:56 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				| nataraj: Now try to solve it without using the XY-Wing cells. | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		Asellus
 
 
  Joined: 05 Jun 2007 Posts: 865 Location: Sonoma County, CA, USA
  | 
		
			
				 Posted: Sun Oct 26, 2008 11:15 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				Two steps:
 
 
[1] Using the 16 UR in r13c59:
 
(8)r1c4|r7c2 - UR[(8)r13c5=(7)r3c5] - (7)r2c6=(7)r4c6 - (7=1)r6c4 - (1=8)r7c4 - (8)r1c4|r7c2; r1c4|r7c2<>8
 
 
This opens up a...
 
 
[2] 13 W-Wing, c46: r2c6|r9c4<>3 | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		 |